1: Don't be a dick.
If you feel like you shouldn't be doing something, you're probably right.
Going out of your way to ruin rounds will end with you dead at best, banned at worst. If admins believe you only play to ruin rounds, you will be banned.
Sabotaging parts of the station, releasing hostile mobs and causing chaos for no reason counts as being a dick.
Do not start fights or chaos on the Emergency Shuttle unless the round has already ended.
Excessively linetoeing/"rules lawyering" to be a dick will get you banned.
Jobs like the Clown and Mime are given more leeway on grief, but are still bound to this rule.
Under Declaration of War, don't grief in general.

2: Validity and EscalationUnder no circumstance are you not allowed to fight back.
When you engage in a fight, you have two options. You can choose to disengage and become a victim, which will allow admins to help you, or you can choose to fight back.
Even if the other player was the aggressor, if you fight back lethally and happen to die, it's most likely valid.
Don't kill Security just for doing their job. Feel free to fight if you get permabrigged or if Security is trying to kill you, otherwise don't attack them for brigging you for three minutes.
Security should abstain from killing people or grief unless absolutely necessary, or the target is an antagonist. Brig people instead.
A good rule of thumb is "eye for an eye." Beating a guy up if they're constantly annoying you, even if this escalates to critting, is fine. But if they only disarmed you twice then stopped, don't murder them.
If you start fights, play stupid games with people, or generally act like a retard then don't cry to admins when you die.
If you are a Catbeast (Tarajan/Tajaran), read erotic copypastas out loud, or a Cluwne, you are valid. Catbeasts and copypasta-readers cannot defend themselves lethally, nor can they cuff assailants or grief under any means.
Threatening to call admins on someone will get you mocked and ignored, or worse.

2.5: Antagonist Rules
Antagonists do not have to obey Rule 1, or anything written above Rule 2.5. This does not mean you aren't valid to other players if you're a catbeast/copypasta reader/cluwne/etc.
Antagonists are valid once they do anything wrong, even if it's just as simple as buying or possessing antagonist gear.
Do not grief your teammates at all, at least without an extremely good reason. You should know who your teammates are based on the icon to the right of their sprite.
Do not spawncamp arrivals.

3: Hippiestation is Low/Lax Roleplay
Roleplaying is not enforced outside of a few conditions:
Each round is a fresh and new one.
Don't talk about the current round in OOC unless it has ended.
Don't have a pants-on-head retarded name. Antagonists, Clowns and Mimes are excused from this.
Don't use emoticons, parenthesis, usernames/ckeys, or leetspeak in IC.
No forced erotic roleplay.
You can insult admins all you want, but do it IC and you might end up unleashing the wrath of a bored, drunk admin.Metagaming is strictly forbidden:
Do not use information you've gained while dead. (e.g. who the antagonists are, where your killer is).
If you are teaching a friend how to play, adminhelp first or risk being banned for metacommunication.
Metacommunication is using an external chat or voice over IP client to talk about the current round.
Metafriending is the act of retaining friendships from past rounds. Conversely, Metagrudging is the act of holding grudges over rounds.
Punishments for metagaming will be particularly severe. Metacomms will always result in a permanent ban.

4: Obey your laws as a silicon.
A "silicon" would be defined as the AI, Cyborgs, or Drones. If you have laws, you're a silicon.
Laws take priority in the order that they are listed, top to bottom.
Silicons are not anchored to Rule 1 or Rule 2. Rule 2.5 still applies to silicon antagonists. Your laws are otherwise replacements for those rules.
You can still freely murder catbeasts, cluwnes, and copypasta readers regardless of lawset.
You can loophole every law you get, unless you are currently emagged. Loopholing default lawsets in order to be annoying will get you killed at best, banned at worst.
Roundstart races count as human under asimov.
Vampires and Pillar Men are not human, any roles or antagonists that do not spawn on the station are not crew.

As draconian as it sounds, Hippiestation Admins have the final say on what stays and what goes.

If you believe that an admins idea of the rules is about as retarded as an autistic twelve year old with down syndrome and late-stage creutzfeldt-jakob disease's idea of quantum physics, then go to Admin Complaints.
If you think you were punished unfairly, or can prove that your dog did in fact get on your computer and grief the server, then go to Ban Appeals